(not present in the paper - the following is the "Introduction") Dehydrocholic acid (DHCA) represents an important aid in the dietary supplement industry because of its choleretic activity; it is less toxic to the natural bile acids. It is not a natural component in bile acids and it is generally produced by chemical oxidation of cholic acid (CA). On an industrial scale, the chemical oxidation of CA is carried out by liquid bromine or calcium hypochlorite. The yield of these processes is satisfactory, but they involve considerable amounts of byproducts, whose separation and disposal may represent a problem. Recently, biotransformations have also been applied to the synthesis of DHCA from cattle bile. Yields were, however, rather low and the process lengthy. In this context, electrosynthesis may represent an interesting alternative, possibly allowing higher yields, good selectivity and minimal byproducts. In the present work, mediated electrochemical oxidation of the secondary alcoholic functions of CA has been attempted, because of the inherent high oxidation potential of the hydroxyl group. The process has been investigated at different electrode materials, such as galvanic platinum, Ti-supported lead dioxide and graphite, and operating both in alkaline aqueous solution and ethylene glycol dimethyl ether (mono-glyme)/water mixture.
Electrosynthesis of dehydrocholic acid from cholic acid
DE BATTISTI, Achille;FERRO, Sergio;MEDICI, Alessandro;PEDRINI, Paola
2000
Abstract
(not present in the paper - the following is the "Introduction") Dehydrocholic acid (DHCA) represents an important aid in the dietary supplement industry because of its choleretic activity; it is less toxic to the natural bile acids. It is not a natural component in bile acids and it is generally produced by chemical oxidation of cholic acid (CA). On an industrial scale, the chemical oxidation of CA is carried out by liquid bromine or calcium hypochlorite. The yield of these processes is satisfactory, but they involve considerable amounts of byproducts, whose separation and disposal may represent a problem. Recently, biotransformations have also been applied to the synthesis of DHCA from cattle bile. Yields were, however, rather low and the process lengthy. In this context, electrosynthesis may represent an interesting alternative, possibly allowing higher yields, good selectivity and minimal byproducts. In the present work, mediated electrochemical oxidation of the secondary alcoholic functions of CA has been attempted, because of the inherent high oxidation potential of the hydroxyl group. The process has been investigated at different electrode materials, such as galvanic platinum, Ti-supported lead dioxide and graphite, and operating both in alkaline aqueous solution and ethylene glycol dimethyl ether (mono-glyme)/water mixture.I documenti in SFERA sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
